/Engine/Source/Developer/AssetTools/Public/IAssetTools.h
Unregisters an asset type actions object. It will no longer provide information about or actions for asset types.
void UnregisterAssetTypeActions ( const [TSharedRef](API\Runtime\Core\Templates\TSharedRef)< [IAssetTypeActions](API\Developer\AssetTools\IAssetTypeActions) > & ActionsToRemove )